1. Field of the Invention
The present invention relates to an aerodynamic device for a vehicle for adjusting the flow of air of a wheel house.
2. Description of the Related Art
It is known that, as an automobile travels, the air which flows into the wheel house is blown-out to the side of the front wheel, and disturbs the flow of air at the side of the front wheel. Specifically, at an automobile S2 shown in FIG. 10, the distance, along the vehicle longitudinal direction, between the front portion (a fender liner 20) of a wheel arch 12A and a front surface side of a front wheel 15 is substantially constant regardless of the vehicle speed. The air which hits the front surface of the front wheel 15 is sucked-into the front portion of a wheel house 16 by the negative pressure which arises accompanying the traveling, and flows-in to the interior of the wheel house 16. Due to the flow path, within the wheel house 16, of the air which flows-in (the space between the front wheel 15 and the fender liner 20) being narrow, the flow speed downstream of this negative pressure portion suddenly drops, and a relatively high-pressure region H shown in FIG. 10 is generated. In this way, the air which reaches region H overflows, and is blown-out from the opening portion of the wheel house 16 which is directed toward the outer side in the vehicle transverse direction, i.e., from between the wheel arch 12A and the front wheel 15. In this way, the air flow at the side of the front wheel 15 is disturbed, and the air resistance increases. Note that reference numeral 12 in the drawing denotes a front fender panel, reference numeral 18 denotes a front bumper, and reference numeral 18A denotes a bumper cover.
A technique is known (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 8-318876) which provides a movable wheel arch fairing for enabling expansion and contraction of the interval between the wheel and the wheel arch. When the vehicle travels at high speed, the wheel arch fairing is in a state of usage in which it protrudes-out beneath the wheel arch, and suppresses the drawing-in of air into the wheel arch. When the vehicle is traveling off-road, the wheel arch fairing is in a housed state in which it is housed in the wheel arch, and permits a large stroke of the wheel.
However, in the conventional technique such as described above, the wheel arch fairing is merely a structure which opens and closes the opening end at the side of the wheel house, i.e., the entrance/exit of air. Therefore, it is difficult to suppress the inflow of air into the wheel house from between the fender liner and the front wheel which accompanies traveling of the vehicle, and there is room for improving on the increase in air resistance caused by air being blown-out to the side of the front wheel.